Various systems have been designed to allow automatic (driverless) operation of rapid transit vehicles in mainline revenue service (i.e., passenger carrying operations) using a fixed block design.
In a fixed block design (as shown in FIG. 3 attached hereto) the guideway is divided into segments called blocks. Such a design can be appreciated from U.S. Pat. No. 4,166,599, assigned to the assignee of the present invention, the disclosure of which is incorporated herein by reference.
In the system briefly described in U.S. Pat. No. 4,166,599 as prior art, and illustrated here in FIG. 3, block boundaries are identified by short vertical strokes through the horizontal line identifying the guideway. The arrows indicate information transfer capability, and the shorthand "DP" refers to data processing.
An apparatus is arranged in each block, for detecting the presence of a vehicle in that block. This wayside apparatus may be coupled to wayside apparatus of one or more adjacent upstream blocks for the purpose of informing vehicles in such upstream blocks of the presence of a vehicle in a downstream block. In one specific application, for example, the block directly upstream of an occupied block is provided with a signal requiring an emergency stop. The next adjacent upstream block is provided with a signal requiring a stop, the next adjacent upstream block is provided with a signal calling for a low speed, and so on. In effect, an information communication arrangement is combined with distributed wayside data processing or computing. In such a system, the vehicle headway, i.e., the distance between moving vehicles, is at least one block long, and may, in normal practice, be two or more blocks long.
Another system is called the moving block design (as shown in FIG. 4 attached hereto), wherein each vehicle that is being controlled, transmits its location to a controlling authority, usually on a periodic basis. Thus, the controlling authority has available to it information as to the location and, perhaps speed, of all the vehicles being controlled. Under these circumstances, the controlling authority then provides signals to the vehicles, based upon downstream traffic conditions, allowing the vehicles to proceed at safe speeds, or on the other hand, requiring the vehicles to stop.
A third method for automatic (driverless) operation of rapid transit vehicles in mainline revenue service is set forth in the already cited U.S. Pat. No. 4,166,599. This patent discloses a control system in which each vehicle has provided to it information regarding the next adjacent downstream occupied or unavailable block; the system relies on distributed (i.e., vehicle carried) data processing or computing. This system avoids the need for multiple communication channels required by the moving block approach. At the same time, however, the single communication channel may provide to any vehicle the identity of the block it occupies, the identity of the next adjacent downstream occupied or unavailable block, and the speed of the vehicle in such block. With this information, the upstream vehicle's headway can be reduced to approach the headway achievable in moving block systems.
The practice of automatic (driverless) operation of rapid transit vehicles has not been extended to yard operations. Current systems for parking and storing rapid transit vehicles in railway yards require a driver to move the vehicles through the yard and perform the parking, coupling and uncoupling maneuvers. The use of drivers for parking and storing of rapid transit vehicles is both costly and inefficient. It is, therefore, highly desirable to incorporate an automatic (driverless) operation in yard operations.
The present invention resides in a system in which the automatic operation is continued from the mainline revenue service to the railway yard for driverless parking and storage of rapid transit vehicles. The present invention provides the following advantages over conventional systems for parking rapid transit vehicles in a railway yard: (1) allows safe driverless operation within yard limits; (2) vehicles can be stored singly or in multiple vehicle consists which reduces the number of required coupling and uncoupling moves; (3) vehicles can be automatically coupled and uncoupled under control of a non-vital yard computer; (4) vehicles can be closely parked reducing required yard area; (5) allows use of profile stop command interlocked with adjacent storage tracks and entry/exit tracks (and time limited operation); (6) distributed system allows fallback operation in the event of a single component failure (as opposed to moving block system); and (7) allows use of same on board equipment as in revenue service.
Additional advantages of the present invention shall become apparent as described below.